class Point {
	double x, y,z;
	public Point(double _x, double _y, double _z) {
		x = _x;
		y = _y;	
        z = _z;
	}
	public double getDistance(Point p) {
		return Math.sqrt((x - p.x) * (x - p.x) + (y - p.y) * (y - p.y)+(z - p.z)*(z - p.z));
	}
}
class Test {
	public static void main(String[] args) {
		Point p = new Point(3.0, 4.0, 9.0);
		Point origin = new Point(0.0, 0.0,0.0);
		System.out.println(p.getDistance(origin));
	}
}